1. Field of the Invention
The present invention relates to a motor including an insulator.
2. Description of the Related Art
In general, motors include a rotor and a stator. The stator is typically attached to a cylindrical bearing housing containing a bearing. The stator typically includes a stator core and an insulator attached to the stator core.
The rotor is arranged to rotate relative to the stator. The rotor typically includes a boss portion and a shaft having one end fixed to the boss portion. The shaft is inserted inside the bearing housing, and rotatably supported by the bearing.
For example, a motor described in JP-A 2003-47222 has a mechanism to prevent the shaft from coming off the bearing housing.
In such a conventional motor, however, when viewed in an axial direction, both an inner circumferential surface of the insulator and an outside surface of a cylindrical intruding portion are in the shape of a circle having a single radius. Therefore, upon application of a shock or the like from outside, a stopper portion and the cylindrical intruding portion may be forced out of engagement with each other such that the shaft comes off the bearing or the insulator regardless of relative circumferential orientations of the cylindrical intruding portion and the stopper portion.